The Tacuinum Sanitatis is a medieval handbook on wellness, based on the "Tables of Health", an eleventh-century Arab medical treatise by Ibn Butlan of Baghdad.
It sets forth the six essential elements for well-being:
-sufficient food and drink in moderation,
-alternations of activity and rest,
-alternations of sleep and wakefulness,
-secretions and excretions of humours and finally,
-the effects of states of mind.
Illnesses result from imbalance of these elements, therefore a healthy life is lived in harmony.